Hα imaging survey of galaxies within 10 Mpc

“Nearby Dwarf Galaxies” SAO RAS, September 14-18 2009

byIgor D.Karachentsev & Serafim S. Kaisin

Special Astrophysical Observatory

Russian Academy of Sciences

Growth of the Local Volume sample (D < 10 Mpc)

Year Reference Number

------------------------------------------- 1979 Kraan-Korteweg & Tammann 179

1994 Karachentsev 215

2004 Karachentsev et al.=CNG 451

2009 current version of CNG 730

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Basic contributions to the Hα survey of the LV galaxies

Authors Year Reference NLV Sample

------------------------------------------------------------------------------------------------------------------------ Kennicutt & Kent 1983 AJ, 88, 1094 25 S,Ir Kennicutt et al. 1989 ApJ, 337, 761 14 S,Ir Hunter et al. 1993 AJ, 106, 1797 37 Ir Miller & Hodge 1994 ApJ, 427, 656 11 M81 group Young et al. 1996 AJ, 112, 1903 16 S

van Zee 2000 AJ, 119, 2757 15 Ir isolated Bell & Kennicutt 2001 ApJ, 548, 681 24 S,Ir Gil de Paz et al. 2003 ApJS, 147, 29 10 BCD James et al. 2004 A&A, 414, 23 49 SO/a - Im Hunter & Elmegreen 2004 AJ, 128, 2170 50 Im, BCD

Meurer et al. 2006 ApJS, 165, 307 10 HIPASS selected Epinat et al. 2008 MNRAS, 390, 466 27 S Kennicutt et al. 2008 ApJS, 178, 247 171 T>-1, B <15m,|b|>20° Bouchard et al. 2009 AJ, 137, 3038 18 Scu & CenA groups Karachentsev & Kaisin 2005 - 2010 207 All types ------------------------------------------------------------------------------------------------------------------------

Basic relations

SFR(M/yr) = 1.27 · 109 FC (Hα) · D2 — Gallagher et all. (1984), where D is distance in Mpc,

FC is flux in (erg· cm-2· sec-1 ) corrected for the Galactic (Schlegel et all. 1998) and internal extinction

A(Hα) = 0.538·AB

Aint =[1.6+2.8(logVm -2.2)] · log(a/b), if Vm > 42.7 km/c, otherwise Aint = 0

Log(MHI/ M) = log FHI + 5.37 +2 · log DMpc

PK=log([SFR]·T0/LK), F=log(MHI/[SFR]·T0)

K – magnitudes from 2MASS or via:

<B-K> =4.10 for T≤ 2 {E, SO, Sa)

<B-K> =4.60 – 0.25 ·T for T= 3-8

<B-K> =2.35 for T=9,10 (Sm, BCD, Ir)

Hα view of the Garland from the 6-m telescope

Hα view of the UA281 from the 6-m telescope

Hα view of the NGC4460 from the 6-m telescope

Stinson, Dalcanton et al. (2007, ApJ, 667, 170) simulated the collapse of isolated dIr's with effects of SN feedback. They found cyclic SF bursts on a scale of ~0.3 Gyr with a SFR- amplitude about 10 times for low mass dwarfs having Vm < 20 km/s.

Hα view of the NGC4449 from the 6-m telescope

Hα view of the DDO125 from the 6-m telescope

Hα view of the DDO181 from the 6-m telescope

Hα view of the UGC8215 from the 6-m telescope

The total star formation rate density in the Local universe( Z = 0, Ho = 72 km/s/Mpc, extinction corrected)

----------------------------------------------------------------------------------------- Log(SFR density) Reference Note

Myr -1 Mpc-3 --------------------------------------------------------------------------------------- -1.95 +/- 0.04 Gallego et al. 1995 em. line gg. -1.73 +/- 0.07 Tresse & Maddox 1998 I-band survey -1.64 +/- 0.02 Perez-Gonzalez et al. 2003 opt.-selected -1.66 +/- 0.08 Brinchmann et al. 2004 SDSS-based -1.81 +/- 0.03 Hanish et al. 2006 HI- selected -1.75 +/- 0.03 Salim et al. 2007 UV-based -1.72 +/- 0.08 James et al. 2008 Hα Local Univ. -1.77 +/- 0.08 present talk Hα Local vol. ----------------------------------------------------------------------------------------

Some cosmic (global) parameters (h = 0.72, Z = 0)

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The critical density: 1.43 ·1011 M/Mpc3 K-luminosity density: 4.6 ·108 L/Mpc3 (Kochanek et al.2001) + (Bell et al. 2003) HI density: 0.55 ·108 M/Mpc3 HIPASSSFR density: 0.017 M/yr Mpc3 present talk PK -0.30 present talkF -0.63 present talk Fcorr -0.36 (+0.17dex HeI, +0.10dex HII)

--------------------------------------------------------------------------------------------------------------------- Cosmic baryon budget (Fukugita, 2003) in the Omega-units:

0.25% (stars) + 0.08% (HI+HeI+H_2) + 0.20% (hot gas in clusters) + 2.2% (warm & cold gas) = 2.7%

versus (4.4+-0.4)% from Big Bang Nucleosynthesis---------------------------------------------------------------------------------------------------------------------

Concluding remarks and questions

• We should aspire to image ALL the LV galaxies in Hα and in HI without any morphological selection.

• Should we try to reach such deep limiting fluxes for survey: F(Hα) = 10-15 (erg/cm2 sec) or log[SFR] = -4.1 at D = 8 Mpc F(HI) = 0.1 Jy·km/sec or log MHI= 6.2 at D = 8 Mpc (competition with data on UV-fluxes from GALEX or EW from Sloan)

• Does the quadrant {PK > 0, F > 0} is almost empty or it contains many hidden objects like HIJASS near IC2574, HI1225+01 in Virgo, and "Leib“ (AGC219303) near NGC3628 ?

• SAO database for the Local Volume galaxies (N = 730) will be ready soon.

HI1225+01 in Virgo

Thanks for your attention